Conductor-insulator clamp



April 6, 1943- D. c. HUBBARD 2,315,961

CONDUCTOR-INSULATOR CLAMP Filed Dec. 1l, 1941 2 Sheets-Sheet l April 6, 1943. D, c. HUBBARD CONDUCTOR-INSULATOR CLAMP Filed Dec.V ll,` 1941 2 Sheets-Sheet Patented Apr. 6, 1943 CONDUC-TOR-INSULATOR CLAMP David C. Hubbard, Centralia, Mo., assigner to A. B. Chance Company, Centralia, Mo., a corporation of Missouri Application December 11, 1941, serial No. 422,476

1c Claims. (Cl. 174-172) The present invention relates to conductorinsulator clamps, and is particularly concerned with the provision offanimprovedsecuring device for securing line conductors to line insulavision of an improved conductor-insulator clamp which is provided with latching means so constructed that there is practically no possibility of the clamp being loosened by vibration or the 'strains to which the conductors or insulators of a transmission line are ordinarily subjected.

Another object of the invention is the provision of an improved conductor-insulator clamp of the class described which is adapted to be secured to the insulator in a plurality of different positions so that its actuating or securing devices may be arranged for convenient engagement with a clamp stick or other line tool.

Another object of the invention is the provision of an improved conductor-insulator clamp adapted to effect a resilient clamping action for securing a conductor to a line insulator having threaded means for regulating the pressure of engagement of the clamp with the conductor and a latching device for positively preventing the release of the threaded means.

Another object of the invention is the provision oiimproved forms of conductor-insulator rclamping devices which are adapted to be quickly and firmly secured against loosening of the `conductor or device from the insulator.

Another object of the invention is the provision of an improved conductor-insulator clamping device which is sturdy, simple, capable of being manufactured at a low cost, and adapted to perform its functions for a long period oi' time without any necessity for repair or replacement of parts.

Another object of the invention is the elimination of the use of the usual copper tie wires lwhich must be installed new each time a conductor is placed or replaced on an insulator.

Another object is the saving of time and expense in the applying and removing of such tie wires from the conductor duringmaintenance work and to increase the safety of the system with respect to operators or line men on account ol the fact that the conductors may be freed from or anchored te an insulator with hot line tools with greater safety when the present invention is employed.

When tiewires vare being removed from an energized line by means of the line tools which are called hot sticks, these tie wires present a considerable length of energized wire Which it is difficult to handle in a safefmanner. The extending length of energized Wire of a tie vwire necessarily waves aboutthrough the air during the process ci unwinding the tie wires from the conductors. Thus at frequent intervals it is desirable or necessary to stop untying operations long enough to use a pair of insulated connectors to cut ori the unraveled length oi the wire.

Even with this precaution, extreme care is necessary to avoid striking other objects of the unraveling tie wire. In the case of double arm construction there are arming bolts employed at the extreme end oi the arms, and in some cases these bolts are grounded. Contact with such bolts would short circuit the line being worked on, causing a dangerous condition to the lineman and defeating the purpose of operating on the line without affecting its condition of energization.

This is only one of the special difficulties that may be encountered in the process of unwinding such tie wires, and these diculties are eliminated when the present clamping arrangement is used.

Otherf objects and advantages of the invention will be apparentfrom the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the two sheets of drawings accompanying the specification,

Fig. 1 is a fragmentary plan View of a line installation showing the application of the present conductor-insulator clamp in such manner that vthe kcross arm will not interfere, with the use of a clamp stick for engaging the eye of the clamping device; l I Fig. 2 is a side elevational view of a conductorinsulator clamp embodying my invention;

(Fig. 3 is a similar view of a modification;

Fig. 4 is a top plan view of the device of Fig. 3; Fig. 5 is a top plan View of the device of Fig. 2. Referring to Fig. 1, Hl indicates a line pole which is equipped with aconventional cross arm I I carrying a plurality of insulators, one of which is indicated at l2. f

The line conductor is carried by the insulator l2, and is indicated by the numeral 8l, and I4 v indicates the conductor-insulator clamping device embodyingy my invention.

Referring to Figs. 2 and 5, the conductor-insulator clamp is here shown in greater detail. It preferably comprises a conductor engaging arm I5, which is pivotally mounted upon a collar I6 carried by the insulator I2. It also comprises a threaded member or extension I1 of the arm I5, which is provided with a threaded member or nut I8 for securing the arm I5 in clamping position.

The present device is preferably adapted to be used with standard line insulators of the type used on high voltage transmission lines, but it may, of course, be employed with any type of insulator on any type of line.

The insulators above-mentioned are usually provided with a member I9 having a transverse conductor-receiving groove 25 in the upper face 2I of the head I9.

Below the head I9 there is located a tie wire groove 2I', and the insulator usually has one or more skirts 22. The clamping device is provided with means for permanently securing it to the insulator I2, such as, for example, the clamping collar, which may consist of two similar parts.

In the embodiment illustrated (see Fig. the clamping collar I6 consists of a pair of similar parts, which may be constructed of cast metal, each of which has a semi-circular portion 23 and a pair of radially extending flanges 24, 25 at each end.

While the portion 23 has been described as semi-circular, it preferably embraces less than half the periphery of the insulator groove 2I so that the anges 24, 25 may be suitably spaced from each other to be secured together by the bolts 26, 21.

For this purpose the anges 24, 25 are each provided with the bolt apertures 28, 29, the apertures being in registry in the flanges 24 and in the iianges 25. A nut on each of these bolts and a spring washer 3I are used for urging the two half circular members 23 together to clamp them on the insulator in the groove 2 I.

This collar I6 is preferably a relatively permanent attachment on the insulator, as it may be placed on the insulator at the time the line is copstructed, and may remain on the insulator until the line is entirely dismantled; but the device is preferably provided with means for securing the conductor in such manner that the conductor can be quickly removed or reattached to the insulator.

This means is preferably in the form of a pivoted lever I5, which may comprise a strip or bar of metal formed with a cylindrical bearing portion 32 at its right end in Fig. 5 for pivotal mounting on the bolt 26.

In order to provide a suficient body of material for this purpose the arm I5 may comprise a strip of metal which is substantially wider than its thickness so that it can be bent in the direction of its smallest dimension about the bolt 2B.

At its opposite end the arm l5 (Fig. 5) is provided with a longitudinally extending slot 33, separating the two bearing portions 34, 35, which carry the pintle 36 in the form of a rivet. The rivet 36 may pivotally support the shank I1 of a screw bolt having a threaded portion 38 for engagement with a threaded member I8.

The pivotal mounting of the bolt I1 at 3S on the arm I5 permits an independent adjustment of the position of the bolt I1 so that its threaded member I8 may engage flatly against the edges of the retaining flanges 24 on the collar I6.

The anges 24 on the collar I6 project laterally and substantially parallel to each other, and are secured together by the bolt 21, and they prefrably project diagonally upwardly beyond the bolt 21 to serve as retaining flanges for the threaded member I6.

The flanges 24 are spaced sufliciently to receive the bolt 21 between them, and their lower edges 39 engage the fiat or plane face 4!) of the threaded member I8.

The threaded member I8 may comprise a cast metal member having a substantially cylindrical body portion 4 I, which is provided with the plane end surface 40 and with an axial threaded bore 42.

To save material, there may be an opening formed at 43 in the body 4I, into which the bolt I1 projects. The body 4I is preferably provided with an eye portion 44 formed 'by an integral toroidal extension, the opening of which is indicated at 45. The eye 45 is preferably of the same size as the eye of a standard hot Wire clamp so that it may be engaged by ordinary clamp sticks, but in some embodiments of the invention the eye may be of larger size, where it is not intended to be received in the socket of a clamp stick.

In order to secure the threaded member I8 against any rotative motion, its plane surface 40 is preferably provided with one or more axially projecting ribs 46, 41.

These ribs may be of substantially rectangular cross section, but they are preferably slightly tapered at their sides 48 so as to facilitate their camming the threaded member away from the retaining iianges 24 when the threaded member is actuated by a clamp stick.

The ribs 46, 41 are located between the flanges 24 when the device is in clamping position, and act as positive stops for engaging the flanges 24 and preventing rotation of the threaded member I8 except by the application of a predetermined rotative force with a clamp stick or other tool.

Referring to Fig. 3, in this embodiment the shank of the bolt I1 is not threaded at its lower end, but is provided with a transverse pintle, preferably in the form of a rivet 49.

'I'he eye 45 has its body portion 50 bifurcated by means of a longitudinal slot 5I, which separates it into two anges 52, 53, The anges 52, 53 are provided with the apertures 54 for receiving the rivet 49, whereby the body is pivotally mounted on the bolt I7, which is in the nature of a connecting rod.

The slot 5I preferably extends only into the top, and not all the way through the body, with suilicient clearance to permit a pivotal movement of the body 50 on the connecting rod I1, and with a stop surface engaging the lower side 56 of the connecting rod I 1 when the parts are in the position of Fig. 3.

Thus the eye member 51 is pivoted on the rod I1 for a limited amount of pivotal movement, and when it reaches the position of Fig. 3, the eye member 51 is adapted to exert a downward pull on the rod I1 to pivot it counterclockwise.

The side flanges 52, 53 of the body 5 are preferably provided with the camming surfaces 58 of the same curvature, the radius of which increases from the point 55 to the point 6D. The end of the body 56 may be provided with a at surface 5I.

The collar I6 has a pair of upwardly extending retaining flanges B2, which are joined by the bolt 63, and which extend parallel to each other, but are spaced sufficiently to receive the connecting rod I1.

The lower edge 64 of the flanges 62 is preferably straight and plane and adapted to engage the fiat surface 6I on the ring body 5I).r

The arm l5 is preferably provided with a diagonally upwardly extending portion E5. and a horizontally extending portion 66. The horizontally extending portion 66v may be provided with an enlargement 61, forming a pair of spaced bearings 68, B9 for a pintle 10 by means of which the arm I5 is connected to'a connecting rod I1.

The connecting rod has a similar bearing portion 1I, which ts between the bearing portions 68, 69. At its opposite end the arm I5' is provided with an enlargement or bearing portion 12, having a transverse bore 13 for rreceiving the screw bolt 14. At this end the collar I6 has its parts provided with a pair of substantially parallel flanges 15, which extend substantially horizontally. f

Between the end flanges I6 and 15 the collars I6 are provided with partially spherical portions 16, which are of such curvature that they nt in the groove v2| of the insulator I2 so that this collar may be xedly' clamped on the insulator by means of the bolts 63 and 14.

The horizontal; portion 66 of the lever I5 is preferably provided with a conductor-engaging shoe 11 of metal' or other material. This shoe is xedly secured to a threaded member 18, which taining the alignment. of the shoe v1 1 with the I vconductor 8|. The shoe may be Supplied in metal closely related to thev conductor material, such as, for example, a brass shoe may be used for copper conductors, and an aluminum shoe for aluminum conductors.. a galvanized shoe for steel or aluminum conductors, etc. By this arrangement electrolytio corrosion between the shoe andthe conductor ris avoided.

since the shoe is pivotally mounted on the arm I5, it may extend at any angle, and the collar I6 may be clamped diagonally on the insulator I2 with respect to the cross arm II.

` Thus the eye member 45 may extend out toward one side of the cross arm to be engaged conveniently by a clamp stick. This prevents the cross arm I I from interfering with, the operation of ythe clamp stick in actuating theY eye.

rIfhe operation of this embodiment of the invention is substantially the same as that previously described, except that in this case there is a cam action at the surface 58 for tightening the arm I5 against the conductor, and the flat surface 6I serves as a latching surface for holding the device in latching position.

When a conductor is to be secured to an insulator and the device itself has already been mounted on the insulator by means of its collar I6, the conductor is placed in the insulator groove 20; and a clamp stick having been secured tothe eye 45, the arm I5 is pulled downv against the conductor so that its shoe engages the conductor 8I.

The eye member 51 may be pivoted upward in a counterclockwise direction in Fig. 3 until the connecting rod I1 passes down between the anges 62. Then a downward pull on the eye 45; will cause the camming surface 58 to slide against the lower edge portions of the flanges 62; and as the radius of the cam .faitk increases, the connecting rod I1 will be pulled'and the resilient arm I5. drawn into tight engagement with the conductor 8 I, which will be forced against the. insulator I2. y

As the curved camming surface 58 passes out of engagement with the flanges v62, the flat portion 6I comes into engagement with the flanges 62', and the connecting rod I1 drops backward slightly, relieving the tension of the arm I5 slight- 1y;- but still maintaining it in tight engagement with the conductor and insulator.

The surface 6I on the eye member 51 serves as a latching surface, as it requires a definite force applied to the eye 45 in a clockwise direction to pivot this member upward from the position of Fig. 3. Thus there is a snap action in the release of the device of Fig. 3, as the eye member 51 pivots upward. There is also a snap action in the device of Fig. 2 as the eye member 4I is rotated and the stop members 45 are cammed out of the space between the flanges 62;

It will thus be observed that I have invented an improved conductor-insulator clamping device which is provided with an improved form of securing device that cannot ypossibly become loosened by vibration or by the application of force to the line or pole or insulator.

The present devices open and close with a snap action, and are definitely held in the closed position. The conductor is resiliently clamped on the insulator, but it may be removed at any time and as often as desired, Without necessity for using a new clamp.

The expense incident to the destruction of an old tie Wire and the use of a new one, in the removal of a conductor from an insulator, is entirely eliminated.

The present clamping devices may be so ar ranged on an insulator that the eye extends toward one side of the cross arm, where it may be more conveniently engaged by a clamp stick. The clamping device may be providedA with conductor-engaging shoesy of appropriate metal, depending on the metal used in the transmission line. conductor.

While I' have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the Lprecise details of construction set forth, but desire to avail myself of all changes within the scope of' the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters VPatent of the United States, is:

1. In a conductor-insulator clamp for electric lines,'the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator', with a resilient arm pivotally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connecting rod pivctally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means adapted to engage a line conductor carried by said insulator, a connecting rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means for urging said resilient arm into engagement with the conductor on said insulator, said arm having a pivoted shoe for engaging said conductor whereby the arm may be arranged diagonally with respect to the line to avoid interference between a cross arm and the line tools used on said clamp, said shoe having a longitudinally extending groove for engaging said line conductor.

3. In a conductor-insulator clamp for electric lines, the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator, with a resilient arm pivctally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connecting rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means lor urging said resilient arm into engagement with the conductor on said insulator, said securing means comprising a threaded member threadedly engaging said connecting rod, and said threaded member having latching elements drawn into engagement with said clamping means by said resilient arm.

4. In a conductor-insulator clamp lor electric lines, the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator, with a resilient arm pivctally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connecting rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means for urging said resilient aim into engagement with the conductor on said insulator, said securing means comprising a threaded member threadedly engaging said connecting rod, and said threaded member having latching elements drawn into engagement with said `clamping means by said resilient arm, said threaded member having an eye formed therein for engagement with a clamp stick.

5. In a conductor-insulator clamp for electric lines, the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator, with a resilient arm pivotally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connecting rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means for urging said resilient arm into engagement with the conductor on said insulatoig'sald connecting rod having a threaded portion, a threaded eye member on said threaded portion for engaging said clamping means, and said clamping means having a pair of upwardly extending flanges for embracing said rod and engaging said threaded member.

6. In a conductor-insulator clamp for electric lines, the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator, with a resilient arm pivotally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connect-ing rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means for urging said resilient arm into engagement with the conductor on said insulator, said connecting rod having a threaded portion, a threaded eye member on said threaded portion for engaging said clamping means, and said clamping means having a pair of upwardly extending flanges for embracing said rod and engaging said threaded member, said threaded member having a latching shoulder adapted to be receivedr between said flanges to prevent rotation of said threaded member under predetermined conditions.

7. In a conductor-insulator clamp, the combination of a pair of 'collar members of metal, said collar members each being provided with partially circular portions for engagement in the groove of a line insulator, and said collar members having laterally projecting securing flanges extending in substantially parallel positie-n, a threaded member at each oi' the ends of said collar members, said threaded members passing through the collar members to secure them together on the line lnsulator, a conductor engaging arm pivoted onl one of said threaded members and having securing means for engaging said collar members adjacent the other of said threaded members, said securing means comprising a threaded member provided with a shoulder for engagement between the ilanges of said collar members.

8. In a conductor-insulator clamp, the combination of a pair of collar members of metal, said collar members each being provided with partially circular portions for engagement in the groove of a line insulator, and said vcollar members having laterally projecting securing flanges extending in substantially parallel position, a threaded member at each of the ends of said collar members, said threaded members passing through the collar lmembers to secure them together on the line insulator, a conductor engaging arm pivoted on one of said threaded members and having securingmeans for engaging said collar members adjacent the other of said threaded members, said securing means comprising a threaded member provided with a shoulder for engagement between the flanges of said collar members, and said threaded member having an eye formed therein for engagement with a line tool.

9. In a conductor-insulator clamp, the combination of a cast metal insulator collar adapted to be secured in the groove of an insulator, said collar comprising a pair of metal members, each of said metal members having a partially circular portion and a laterally extending flange, said flanges extending parallel to each other at the opposite sides of said collar, two of said flanges being joined by a pivot member, and a resilient metal arm pivotally mounted on said pivot member and extending upward and over the top of the insulator, said arm having a pivoted grooved shoe located thereon to register with the upper groove in the insulator, irrespective of the rotative position of the collar on the insulator, a connecting rod pivotally mounted on said arm, and having a threaded end'extending downward between the other two laterally projecting flanges on said collar, and a complementary threaded member provided with an integral eye adapted to be engaged by a clamp stick or the like threaded on the end of said connecting rod for drawing said arm downward into resilient engagement with the conductor in the insulator groove, said complementary threaded member having a thrust surface for engaging below theadjacent flanges on the collar and having a retaining lug adapted to be received betweennthe flanges on thecollar to latch the threaded member in any o various predetermined positions.

10. In a conductor-insulator clamp for electric lines, the combination of clamping means adapted to be permanently secured in the peripheral groove of an insulator, With a resilient arm pivotally mounted in said clamping means and adapted to engage a line conductor carried by said insulator, a connecting rod pivotally secured to said arm, and securing means carried by said connecting rod and engaging said clamping means for urging said resilient arm into engagement with the conductor on said insulator, said securing means comprising a threaded member threadediy engaging said connecting rod, said threaded member having an eye formed therein for engagement with a clamp stick.

DAVID C. HUBBARD. 

